Geologic map of the Bear River City quadrangle, Box Elder County, Utah (M-151)

By: M. E. Jensen

The Bear River City 7.5-minute quadrangle is located in northern Utah on the eastern margin of the Great Basin. Most of the quadrangle is covered by unconsolidated lacustrine and alluvial deposits that are Quaternary in age. Bedrock is only exposed on and near Little Mountain on the northwest border of the quadrangle. These rocks arc Middle Devonian to Permian in age, and have been affected by Sevier folding and thrust faulting, and Cenozoic normal faulting. No Holocene fault offsets have been found in the quadrangle, although scarps about 4 miles east of the quadrangle along the Brigham City segment of the Wasatch fault zone indicate that several earthquakes have produced surface ruptures during the past 10,000 years. Unconsolidated materials are mostly lacustrine lake-bottom and near-shore deposits of Lake Bonneville and the Great Salt Lake, and alluvial and deltaic deposits of the Malad and Bear Rivers. During the Pleistocene prior to the formation of Lake Bonneville, at least two other lake cycles probably inundated lowlands in the quadrangle.

Other Information:
Published: 1994
Pages: 12 p.
Plates: 2 pl.
Scale: 1:24,000
Location: Box Elder County
Media Type: Paper Map